Despite widespread use of complementary and alternative medicine (CAM) in the US, there exist significant gaps in our knowledge regarding CAM decision-making, efficacy, safety and cost-effectiveness. Several factors contribute to this gap, including: limited communication between patients, conventional care providers, and CAM providers, about CAM use and therapies recommended; the focus on evaluation of efficacy and safety of individual CAM therapies or interventions, making it difficult to extrapolate these results to patterns of real-world multi-modality CAM use in conjunction with conventional therapy; and the limited pragmatic research conducted within existing integrative care centers. With funding support from NCCAM, the Osher Clinical Center (OCC) for Complementary and Integrative Medical Therapies was established in 2007, physically located in the Ambulatory Care Center of Brigham and Women's Hospital (BWH). This recent opening provides a unique window of opportunity to accomplish two aims: To characterize the early evolution of referral and practice patterns and to evaluate various aspects of communication and decision-making surrounding the use of conventional and CAM therapies in real world settings; and to provide important observational evidence concerning the effectiveness of an integrative care team with respect to relevant clinical outcomes for a serious and disabling condition, chronic low back pain (CLBP). The first aim will be assessed from four different perspectives: surveys of new patients to the OCC; surveys of BWH physicians who have referred their patients to the OCC; surveys of physicians at BWH in the same departments as the referring physicians but who have not referred to the OCC at two time points; and in- depth qualitative interviews of dyads of referred patients and their referring physicians. The second aim will be addressed in a prospective, observational cohort study, following 150 OCC patients with CLBP and a comparison group of 150 BWH non-OCC CLBP patients with regard to symptom relief, functional status, satisfaction with care, quality of life, utilization of medical care, and productivity. Qualitative interviews of both CLBP patients, as well as members of the OCC team, will be conducted to characterize the course of patient treatment, both from the perspective of the patients as well as the providers. Results of our patient and physician surveys will provide assessments of knowledge, beliefs, referrals, levels of communication, and barriers and facilitators of CAM use in a hospital setting of an academic medical center, and will track these behaviors over time. Results of our observational study will be used to inform and design a future randomized clinical trial evaluating the efficacy and cost-effectiveness of a model of integrative care for the treatment of CLBP.